1. Field of the Invention
The present invention relates to an aqua-stream and aspirator (AS and A) which is useful in crushing and removing brain tumors during the brain surgery.
2. Description of the Prior Art
Conventionally, a variety of surgical instruments, such as an electric knife, a laser knife, and a CAVITRON ultrasonic surgical aspirator (CUSA), for removing brain tumors has been developed and put to practical use. A problem in using a laser knife is that injuries due to local heat are inevitable in and around the incision line, thus producing a nasty smell and smoke, which would screen the operator's visual field. Further, the use of a laser knife necessitates the operator and nurse to wear glasses to protect their eyes from laser light. An electric knife is available for only a limited use. Partly because its hand-piece is large in size and heavy in weight, and partly because the action of ultrasonic wave would be spread to even adjacent normal tissue, a CUSA is not suitable for a delicate operation.
In addition, an aqua-stream and aspirator (AS and A) utilizing a water stream is known for hepatic surgery. However, in this prior apparatus, partly because its entire structure is large-sized, and partly because pressurized water is ejected perpendicularly to the surface the affected part, there is a fear that even normal tissue could be crushed. Consequently the prior apparatus cannot be used for a delicate and precise operation which is required such as in cerebral surgery.